The present invention relates to apparatus and method thereof for handling hazardous materials in general and in particular to a drainage control device for preventing accidental spills of hazardous materials from entering a sewer drain.
Among the most serious problems associated with the handling of hazardous materials is the accidental discharge of such materials into a sewer drain which leads to a sewage treatment plant not equipped to handle such materials, or an accidental discharge of the hazardous material into a storm drain which ultimately flows into a creek, river, lake, bay, or the like. In either case, the cost of containing and cleaning up the material can be enormous both financially and environmentally.
The manufacture of semiconductor products, for example, involves the use of hazardous materials which are usually stored in tanks outside the manufacturing facility. Many times, storm drains and sewer drains are located next to or near the vicinity of these storage tanks. The hazardous material in the tanks is periodically replenished, and removal by waste removal crews creates a risk that, through negligence or by accident, the hazardous material may be spilled onto the ground during the removal or filling of the tanks which could be flow to a nearby storm or sewer drain, resulting in the above-described adverse consequences.
Presently, companies seek to prevent the loss of hazardous materials in a storm drain by covering the drain with an absorbent blanket, such as a SPILL MAT made by Lab Safety Supply of Janesville, Wis., or by surrounding the drain with piles of absorbent material, such as SAFE-T-SORB, available from Orchard Supply Hardware, Sunnyvale, Calif., either before an accidental spill as a preventive measure or afterwards to minimize the damage caused by the spill. Sometimes the edges of the blanket are required to be held down by some sort of heavy object such as, for example, bags of absorbent material.
When the spilled material is a liquid, the use of a bag of absorbent material, or the like, to prevent the liquid material from flowing beneath the edges of the blanket is not always successful. Furthermore, the absorbent blankets which are currently being used for this purpose are expensive and must be replaced as soon as they have become saturated with any liquid, including ordinary rainwater, because, after they are saturated, they no longer will hold any additional liquid.
Also the need to hold down the edges with heavy objects is time consuming and labor intensive. Moreover, when not used to cover a drain, the blanket is usually stored in a pile immediately adjacent to the drain and is therefore unsightly. Alternatively, if the drain is in a traffic area and the blanket can pose an obstacle to traffic. Further, the blanket must be stored some distance from the drain, and thus is likely not to be immediately available for use in case of a spill. When loose material is used to absorb a spill, the material must be cleaned up after a spill or even after a rain. In the interim, the area is unsightly and loose particles of the absorbent material carrying the hazardous material can wash down the drain.
Currently, storm drains modified with catch basins, such as Safe Drain (U.S. Pat. No. 5,383,745 to Shannon) manufactured by Spill Safe(copyright) of San Jose, Calif., are being used to prevent hazardous materials from entering the drain in the case of an accidental spill near a sewer drain. However, non-hazardous materials, such as unpolluted water, will be unable to pass onto the sewer drain, because the plunger plugs the catch basin drain hole when hazardous materials are present in the basin. This may lead to the catch basin becoming backed up with the contaminants, thus overflowing into the street. Further, solid objects, such as branches, dirt, slurry, etc., may enter the catch basin and cover the drain hole. This results in the drain hole being obstructed, which could prevent the plunger from automatically plugging the drain hole if a hazardous material is later detected in the catch basin.
U.S. Pat. Nos. 5,528,720, and 5,728,294 to Deming, disclose a drain closure apparatus which can sense hazardous materials entering the storm drain and trigger a disc to rotate and close the entrance to the drain. This closure prevents the hazardous materials from entering the sewer system when hazardous materials are present near the closure apparatus. These inventions utilize a disc which rotates to close the drain hole in response to detecting a hazardous material entering the storm drain. Specifically, the disc rotates by a large threaded rod, which could eventually corrode or wear due to constant contact with liquids entering the drain. Further, these inventions incorporate many exposed moving parts which could be expensive to manufacture and replace.
In view of the foregoing, it would be advantageous to have a drain closure apparatus which utilizes a minimum number of exposed moving parts and a quick response time, as well as having the ability to allow non-polluted liquid to enter the drain hole while keeping the polluted material separated from the non-polluted material. Further, it would be advantageous to have a drain closure device which has the capability of detecting and measuring pollution levels of the material present near or in the selective suspension device.
Particularly, an apparatus for controlling a flow of a liquid into a sewer drain comprising a catch basin having a catch basin drain coupled with the sewer drain. In addition, a housing element, having a housing chamber, that is positioned within the catch basin, whereby the housing element is coupled with the catch basin drain in a first fluid-tight manner. The housing element having a porous surface positioned below a predetermined level. A column having a proximal end and a distal end, whereby the column is positioned within the housing element and the proximal end is coupled with the catch basin drain in a second fluid tight manner. The distal end is positioned above the predetermined level and an actuator mechanism is coupled with the column and configured to selectively open and close the column to the flow of the liquid that is entering the catch basin drain.
An apparatus for controlling a flow of a liquid into a sewer drain comprising a housing element having an outer surface. The housing element includes at least one aperture on the outer surface, whereby at least some of the liquid enters the housing through the aperture. A conduit is positioned within the housing element, wherein the conduit is coupled with the sewer drain in a fluid tight manner. An actuator mechanism coupled with the conduit, the actuator mechanism further comprising an actuator and a cap coupled to the actuator, The cap is configured to operate between a first position and a second position, wherein the liquid enters the sewer drain when the cap is in the second position.
An apparatus for controlling a flow of a hazardous material into a sewer drain comprising a housing element having a first end and a second end. The housing element is positioned to have the second end coupled with the sewer drain in a first fluid-tight manner. The housing element has at least one aperture located on the first end for allowing the flow to enter the housing element. A conduit positioned is within the housing element, and the conduit is coupled with the sewer drain in a second fluid tight manner, wherein the flow enters the sewer drain through the conduit. An actuator mechanism is coupled with the conduit, and the actuator is configured to selectively allow and prevent the flow from entering the sewer drain. A membrane is coupled with the housing element, wherein the hazardous material flows through the membrane and is screened by the membrane before entering the conduit.
A method for controlling a flow of a liquid into a sewer drain comprising the steps of providing a housing element coupled with the sewer drain in a first fluid-tight manner and having a porous surface positioned below a predetermined level. In addition, providing a column having a proximal end and a distal end, the column being positioned within the housing element, wherein the proximal end is coupled with the sewer drain in a second fluid tight manner and the distal end is positioned above the predetermined level. Also, coupling an actuator mechanism with the column and configuring the actuator mechanism to selectively open and close the column to the flow of the liquid entering the sewer drain.